Trocar seal system

ABSTRACT

A seal assembly for reception of an elongated surgical instrument is provided which includes a body having at least one opening configured and dimensioned to permit entry of an elongated surgical instrument and defining a central longitudinal axis; a seal member formed of a resilient material and defining an aperture therein, the aperture being configured and dimensioned such that insertion of the surgical instrument into the aperture causes the resilient material defining the aperture to resiliently contact the outer surface of the surgical instrument in a substantially fluid tight manner; and a fabric layer juxtaposed relative to the resilient material. A coating may be applied to the seal member to reduce friction between the seal member and surgical instrumentation inserted therein. The coating is preferably a hydrocyclosiloxane membrane prepared by plasma polymerization process.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of co-pending U.S. Ser.No. 12/546,968, filed Aug. 25, 2009, which is a continuation applicationof U.S. patent application Ser. No. 10/718,195, filed Nov. 20, 2003,which is a continuation application of U.S. patent application Ser. No.10/670,032, filed Sep. 24, 2003, now abandoned, which is a continuationapplication of U.S. patent application Ser. No. 10/165,373, filed Jun.6, 2002, now U.S. Pat. No. 6,702,787, which is a continuationapplication of U.S. patent application Ser. No. 09/527,955, filed Mar.9, 2000, now abandoned, which is a continuation application ofInternational Patent Application No. PCT/US98/08968, filed May 1, 1998,which claims priority from U.S. Provisional Patent Application No.60/045,412, filed May 2, 1997, now expired.

BACKGROUND

1. Technical Field

The present disclosure relates to seal systems of the type adapted toallow the introduction of a surgical instrument into a patient's body.In particular, the disclosure relates to a seal system to be used incombination with a cannula assembly where the cannula assembly isintended for insertion into a patient's body and an instrument isinserted into the patient's body through the cannula.

2. Background of the Related Art

Laparoscopic procedures are performed in the interior of the abdomenthrough a small incision, e.g., through narrow endoscopic tubes orcannulas inserted through a small entrance incision in the skin.Minimally invasive procedures are performed elsewhere in the body, e.g.,in the chest, and are often generally referred to as “endoscopic”procedures. Minimally invasive or endoscopic procedures generallyrequire that any instrumentation inserted into the body be scaled, i.e.provisions must be made to ensure that gases do not enter or exit thebody through the endoscopic incision as, for example, in surgicalprocedures in which the surgical region is insufflated. Moreover,endoscopic procedures often require the surgeon to act on organs,tissues, and vessels far removed from the incision, thereby requiringthat any instruments used in such procedures be relatively long andnarrow.

For such procedures, the introduction of a tube into certain anatomicalcavities such as the abdominal cavity is usually accomplished by use ofa system incorporating a trocar and cannula assembly. A cannula assemblyis formed of a cannula attached to a cannula housing which generallyincludes seal assembly adapted to maintain a seal across the opening ofthe seal assembly both with and without an instrument insertedtherethrough. Since the cannula is in direct communication with theinternal portion of the seal assembly, insertion of the cannula into anopening in the patient's body so as to reach the inner abdominal cavityshould be adapted to maintain a fluid tight interface between theabdominal cavity and the outside atmosphere.

Since minimally invasive surgical procedures in the abdominal cavity ofthe body generally require insufflating gases to raise the cavity wallaway from vital organs, the procedure is usually initiated by use of aVerres needle through which a gas is introduced into the body cavity.The gas provides a slight pressure which raises the wall surface of theperitoneum away from the vital organs thereby providing an adequateregion in which to operate. Thereafter, a trocar assembly which includesa cannula and a trocar or obturator is inserted within the cannula topuncture the peritoneum, i.e. the inner lining of the abdominal cavitywall. The obturator is removed and laparoscopic or endoscopic surgicalinstruments may then be inserted through the cannula to perform surgerywithin the abdominal cavity. The cannula may also be utilized forintroducing tubes into the body as for drainage purposes, for specimenremoval, for diagnostic evaluations, or the like.

In view of the need to maintain the atmospheric integrity of the innerarea of the cavity, a seal assembly for a cannula which permitsintroduction of an obturator and a wide range of surgical instrumentsand which maintains the atmospheric integrity of the inner area of thecavity is desirable. Generally, in the context of insufflatory,minimally invasive surgical procedures, cannula assemblies includestructure(s) that satisfy two sealing requirements. The firstrequirement is to provide a substantially fluid tight seal when aninstrument is not present in the cannula. The second requirement is toprovide a substantially fluid tight seal when an instrument is beingintroduced into or already is present in the cannula. In this regard,there have been a number of attempts in the prior art to provide suchsealing requirements.

U.S. Pat. No. 4,655,752 to Honkanen, et al. teaches a cannula includinga housing and first and second seal members. The first seal member isconically tapered toward the bottom of the housing and has a circularopening in its center, while the second seal is conically tapered andcup shaped. The second seal includes at least one slit to allow for thepassage of instruments.

U.S. Pat. No. 4,929,235 to Merry, et al. teaches a self-sealing catheterintroducer having a sealing mechanism to prevent blood or fluid leakage.The sealing mechanism includes a planar sealing element having a slitand a conical sealing element. The sealing elements are each adapted tosurround a tube.

U.S. Pat. Nos. 4,874,377 and 5,064,416 to Newgard, et al. relate to aself-occluding intravascular cannula assembly in which an elastomericvalving member is positioned transversely to a housing and isperipherally compressed to cause displacement, distortion and/orrheological flow of the elastomeric material. A frustoconical dilatorprojection cooperates with the elastomeric valving member in moving thevalving member to a non-occluding position.

U.S. Pat. No. 5,300,033 to Miller suggests a valve constructionincluding an elastic body having a cylindrical wall with first andsecond walls formed integrally with the cylindrical wall. The secondwall includes a slit to permit passage of a surgical instrument andfirst and second leaflets which define the slit. The leaflets arethicker in cross section to provide an additional closing force at theslit.

A disadvantage of several known seal systems for cannulas concerns thedifficulty encountered in inserting and advancing the surgicalinstrument through the seal unit. In particular, since known elastomericseal members are designed to form and maintain a fluid tight seal aboutthe instrument, the aperture or slit within the seal through which theinstrument is passed is of relatively small or narrow dimension.Further, portions of the seal member defining the aperture are generallythick in cross-section to provide a sufficient closing force of the sealabout the instrument. See, e.g., U.S. Pat. No. 5,300,033. As aconsequence of these design considerations, the level of force needed toinsert and advance the instrument through the seal aperture isincreased, thereby requiring awkward maneuvering on the surgeon's behalfto appropriately position the instrument for the desired surgery.Moreover, known seal systems are generally ineffectual in accommodatinginstruments of differing diameter while maintaining acceptable insertionforces and facilitating the range of desired surgical manipulations,e.g., angular instrument movements and specimen removal.

Accordingly, the present disclosure obviates the disadvantages of theprior art by providing a seal unit or assembly for a cannula assembly,which is capable of forming and maintaining a tight seal aboutinstruments of varying diameters inserted through the cannula and whichincorporates structure to enhance and facilitate passage of theinstrument through the seal unit.

SUMMARY

The present disclosure provides a seal assembly for reception of anelongated surgical instrument, which comprises a body having at leastone opening configured and dimensioned to permit entry of an elongatedsurgical instrument and defining a central longitudinal axis; a sealmember formed of a resilient material and defining an aperture therein,the aperture being configured and dimensioned such that insertion of thesurgical instrument into the aperture causes the resilient materialdefining the aperture to resiliently contact the outer surface of thesurgical instrument in a substantially fluid tight manner; and a fabriclayer juxtaposed relative to the resilient material.

The seal assembly may further include a coating applied to the sealmember to reduce friction between the seal member and surgicalinstrumentation inserted therein. The coating is preferably ahydrocyclosiloxane membrane prepared by plasma polymerization process.

In one aspect of the presently disclosed seal assembly a ring member issecured to the seal member and includes a dampening element disposedbetween a surface of the ring member and a surface of the body.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments are described herein below with reference to thedrawings wherein:

FIG. 1 is a perspective view of one embodiment of a seal assemblyconstructed in accordance with the present disclosure;

FIG. 2 is a perspective view with parts separated showing the variousstructural components of the seal assembly embodiment of FIG. 1;

FIG. 3 is a perspective view of a fabric portion for incorporation intothe seal element of the embodiment of FIG. 1;

FIG. 4 is a cross-sectional view taken along section line 4-4 of FIG. 3;

FIG. 5 is a perspective view of a fully formed seal member for the sealassembly of FIG. 1;

FIG. 6 is a cross-sectional view taken along section line 6-6 of FIG. 5;

FIG. 6A is an alternative embodiment of the seal element of FIG. 6;

FIG. 7 is a cross-sectional view of the seal assembly of FIG. 1;

FIG. 8 is a perspective view of a trocar assembly having the sealassembly of FIG. 1 removably installed thereon;

FIG. 9 is a partial cross-sectional view showing the seal body housingtaken along section line 9-9 of FIG. 8;

FIG. 10 is an alternative embodiment of the seal assembly of the presentdisclosure;

FIG. 11 is a cross-sectional view of a further embodiment of the sealassembly constructed in accordance with the present disclosure;

FIG. 12 is a perspective view of the seal assembly of FIG. 11;

FIG. 13 is a perspective view with parts separated of the seal assemblyembodiment of FIG. 11;

FIG. 14 is a cross-sectional view of a further embodiment of the sealassembly constructed in accordance with the present disclosure; and

FIG. 15 is a perspective view of the seal member of the seal assembly ofFIG. 14.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now in detail to the drawing figures in which like referencenumerals identify similar or identical elements, a first embodiment ofthe seal assembly of the present disclosure is illustrated in FIGS. 1-9,and is designated generally as seal assembly 100.

The presently disclosed seal assembly embodiments contemplate theintroduction of various types of surgical instruments adapted forinsertion through an elongated trocar assembly. Examples of suchinstruments include clip appliers, graspers, dissectors, retractors,staplers, laser fibers, photographic devices, endoscopes andlaparoscopes, tubes, and the like. Such instruments are collectivelyreferred to herein as “instruments”.

Referring to FIG. 2, seal assembly 100 includes a seal member 118disposed within the seal assembly body or housing components 114 and 116which snap fit together by way of flexible tab portions 114 a beingdeflected upon insertion into receiving openings (not shown) formed inhousing component 116. Seal member 118 has a circular array of holesformed therethrough around the periphery of an inner section 118 b.

A two part ring assembly which includes ring members 120 and 122 aresnap fitted together on either side of seal member 118. Ring member 120is disposed adjacent the distally facing surface of seal member 118 andring member 122 is disposed on the proximally facing side of seal member118. Ring 120 is provided with holes 120 a and posts 120 b which arealternately disposed around the ring and are aligned with holes 118 a onseal member 118. Ring 122 is provided with posts 122 a and holes 122 bwhich mate with holes 120 a and posts 120 b of ring member 120,respectively by snap fitting together thereby surrounding inner section118 b. Although rings 120 and 122 are shown having alternating holes andposts, one of the rings could have all holes formed therein while theother ring could have all posts aligned with the holes of the otherring. Additionally, greater or fewer holes and posts may be utilized tosecure the two rings together.

A seal clamp 124 is provided within the housing component 114 and 116and serves to secure the outer periphery of seal member 118 within sealassembly 100 (as best shown in FIG. 7). Seal clamp 124 is provided withfour projecting posts 124 a which fit within openings (FIG. 7) formed onthe proximal side of lower housing 116. Seal clamp 124 also serves tosecure a proximal flange of a lower seal 126 which is provided at thedistal end of lower housing member 116. Lower seal 126 assists in thesecurement of seal assembly 100 to cannula assembly 110.

Referring now to FIGS. 3-6, seal member 118 includes a fabricdisc-shaped portion 128 which is preferably disposed on both theproximal and distal sides of inner section 118 b of seal member 118.Alternatively, fabric section 128 may be disposed on just one of eitherthe proximally facing surface or the distally facing surface of innerportion 118 b, as desired. Fabric portion 128 may be of any suitablefabric, for example, a SPANDEX material containing 20% LYCRA availablefrom Milliken.

In one method of forming the composite seal member 118 with fabricportion 128 a raw, i.e., uncured polyisoprene plug is first compressedinto a flat state, e.g., a flat sheet of polyisoprene. A single layer offabric is positioned on top of the flattened polyisoprene sheet andcompressed into the uncured rubber by any suitable compression processsuch as, for example, calendering. If it is desired to have fabric onboth sides of seal member 118, this process is repeated on the otherside of the polyisoprene sheet. The fabric polyisoprene composite is diecut into circular slugs having an outer diameter and an inner diameterwhich forms a central aperture. The slugs are placed in a hotcompression mold to cure the polyisoprene. This step also serves toextrude the outer portions of seal member 118 which extend outwardlyfrom inner section 118 b.

During the above-described process the bleed-through of the polyisoprenematerial into and/or through the fabric layers is regulated by thedensity of the fabric selected. A greater degree of bleed-through ofpolyisoprene provides greater resistance to fraying of the fabric uponrepeated insertion of instruments through the seal. However, too muchbleed-through of the polyisoprene through the fabric will increasefriction forces upon instruments being inserted through seal member 118.

Referring to FIG. 6A, an alternative embodiment of seal member 118 isshown as seal member 418. Seal member 418 is the same as seal member 118in most aspects except that inner section 418 b is formed to have fabriclayer 428 enveloped between upper and lower polyisoprene layers 418 cand 418 d.

In order to reduce friction between instruments and the seal member,e.g. seal member 118 or seal member 418, as instruments are insertedthrough seal assembly 100, a coating may be applied to the scat member.One coating which has been found particularly effective is ahydrocyclosiloxane membrane prepared by plasma polymerization process.Such a coating is available from Innerdyne, Inc. of Salt Lake City,Utah, U.S.A., and is disclosed in U.S. Pat. No. 5,463,010 which issuedto Hu, et al. on Oct. 31, 1995, the entire contents of which are herebyincorporated by reference.

Referring to FIGS. 7 and 8, seal assembly 100 is used in combinationwith a conventional trocar assembly which includes a cannula assembly110 and a trocar obturator 112. Examples of trocar assemblies in whichthe present seal assembly may be utilized are disclosed in U.S. Pat. No.5,603,702 which issued on Feb. 18, 1997 to Smith et al. and U.S.application Ser. No. 08/546,009 filed Oct. 20, 1995 by Smith et al., theentire contents of each of these disclosures are hereby incorporated byreference.

Seal assembly 100, either alone or in combination with a seal unit/sealassembly internal to cannula assembly 110, provides a substantial sealbetween a body cavity of a patient and the outside atmosphere bothduring and subsequent to insertion of an instrument through the cannula.In this manner, insufflation gases are prevented from escaping throughthe trocar assembly to the outside environment. Seal assembly 100 iscapable of accommodating instruments of varying diameter, e.g., fromabout 5 mm to about 12 mm, while providing a fluid tight seal with theouter diameter of each instrument. The versatility of the presentlydisclosed seal assembly embodiments greatly facilitate endoscopicsurgery, wherein a variety of instruments having different diameters areoften needed during a single surgical procedure.

Seal assembly 100 is preferably detachably mountable to the proximal endof cannula assembly 110. Thus, the surgeon can remove the seal assembly100 from the cannula assembly 110 at any time during the surgicalprocedure and, similarly, mount the seal assembly 100 to the cannulawhen desired in order to provide a sealing engagement with an instrumentto be inserted through the cannula. In addition, seal assembly 100 maybe readily adapted for mounting to conventional cannulas of differingstructures. The detachability of seal assembly 100 from cannula assembly110 facilitates specimen removal through cannula assembly 110. Sealassembly 100 includes a housing which is formed by the snap fittingtogether of end cap 114 and lower housing member 116. Preferably thehousing components of seal assembly 100 are formed of a polycarbonatematerial such as ABS available from the General Electric Company.

FIG. 9 shows an instrument having a shaft 130 inserted through sealassembly 100 and a duck bill valve or “zero” seal valve 132 whichprevents the escape of insufflation gases in the absence of aninstrument in the trocar assembly. As shown in FIG. 9, seal member 118provides a seal about the periphery of shaft 130.

Referring to FIG. 10, an alternate embodiment of seal assembly 100 isdesignated generally as seal assembly 150. Seal assembly 150 is the sameas seal assembly 100 except that an inner planar seal member 152 isdisposed in the distal end of seal assembly 100 to provide additionalsealing capability for instruments having larger diameters. Seal clement152 has an aperture 154 which has a diameter larger than the diameter ofaperture 156 of seal member 118. A further feature illustrated in FIG.10 is a dampening member such as pad 158 which is secured to theproximal surface of ring 122 to dampen the sound created by the impactof the proximal surface of ring 122 with the inner distal facing surfaceof housing component 114. Other dampening member configurations are alsocontemplated. For example, ring 122 may be over-molded with materialsuch as polyisoprene so as to envelope part or all of the ring therebyforming a bumper between the ring and the housing component.

Referring to FIGS. 11-13, a further embodiment of a seal assemblygenerally designated as seal assembly 200 is shown throughout theseveral views. Seal member 218 is configured in an hourglass shape andpreferably includes the fabric portion 228 formed as part of seal member218 in a similar manner as described above. The friction reducingcoating of a hydrocyclosiloxane membrane prepared by plasmapolymerization process noted above may also be utilized to coat thesurfaces of seal member 218.

Referring now to FIGS. 14 and 15, a further embodiment of the sealassembly generally designated as seal assembly 300 is shown. Seal member318 is similar to seal member 118 except that inner portion 318 b isformed in a conical shape with a wider opening directed towards aproximal end of seal assembly 300 and a narrower opening directedtowards distal end of seal assembly 300. The friction reducing coatingof a hydrocyclosiloxane membrane prepared by plasma polymerizationprocess noted above may also be utilized to coat the surfaces of sealmember 318.

It will be understood that various modifications may be made to theembodiments shown herein. Therefore, the above description should not beconstrued as limiting, but merely as exemplifications of preferredembodiments. Those skilled in the art will envision other modificationswithin the scope and spirit of the presently disclosed seal assemblies.

1-22. (canceled)
 23. A surgical access device for permitting insertionof a surgical object into body tissue, comprising: a housing; a cannulaextending from the housing configured and dimensioned for introductioninto the body tissue, the cannula defining a longitudinal passageconfigured and dimensioned to permit insertion of the surgical object,and having proximal and distal ends; a ring assembly mounted to thehousing; a seal member having proximal and distal faces and being atleast partially positioned within the ring assembly, the seal memberincluding an inner portion defining an expandable opening extendingthrough the seal member configured and dimensioned to receive thesurgical object; and a friction reducing member positioned adjacent theproximal face of the seal member.
 24. The surgical access device ofclaim 23, wherein the inner portion of the seal member is conical inconfiguration.
 25. The surgical access device of claim 24, wherein theinner portion of the seal member tapers inwardly in a distal direction.26. The surgical access device of claim 23, wherein the frictionreducing member is disc-shaped in configuration.
 27. The surgical accessdevice of claim 26, wherein the friction reducing member includes one ormore layers of fabric.
 28. The surgical access device of claim 27.wherein the friction reducing member includes a membrane.
 29. Thesurgical access device of claim 28, wherein the membrane includes afriction reducing coating.
 30. The surgical access device of claim 27,wherein the friction reducing member includes a first layer of fabricpositioned adjacent the proximal face of the seal member, and a secondlayer of fabric positioned adjacent the distal face of the seal member.31. The surgical access device of claim 23, wherein the ring assemblyincludes first and second ring members connected in a snap fitarrangement.
 32. The surgical access device of claim 31, wherein thefirst ring member is positioned adjacent the proximal face of the sealmember and the second ring member is positioned adjacent the distal faceof the seal member.
 33. The surgical access device of claim 32, whereinthe first ring member includes at least one hole and at least one post,and the second ring member includes at least one hole and at least onepost, the at least one post of the first ring member being insertableinto the at least one hole of the second ring member, and the at leastone post of the second ring member being insertable into the at leastone hole of the first ring member.
 34. The surgical access device ofclaim 23, further including a resilient member extending radiallyoutward from the ring assembly such that the resilient member ispositioned between the ring assembly and the housing.
 35. The surgicalaccess device of claim 34, wherein the resilient member is sinusoidal inconfiguration.
 36. The surgical access device of claim 34, wherein theresilient member and the seal member include the same material.
 37. Aseal assembly for use during a surgical procedure, the seal assemblycomprising: a ring assembly; a seal member having proximal and distalfaces and being at least partially positioned within the ring assembly,the seal member including an inner portion defining an apertureextending through the seal member adapted to expand from a first opencondition to an expanded second open condition upon insertion of asurgical object; and a friction reducing member positioned adjacent theproximal face of the seal member.
 38. The seal assembly of claim 37,wherein the inner portion of the seal member is conical inconfiguration.
 39. The seal assembly of claim 38, wherein the innerportion of the seal member tapers inwardly in a distal direction. 40.The seal assembly of claim 37, wherein the friction reducing member isdisc shaped in configuration.
 41. The seal assembly of claim 41, whereinthe friction reducing member is formed as one or more layers of fabric.42. The seal assembly of claim 41, wherein the friction reducing memberincludes a friction reducing coating.